Hand automatic sampler and diluter

ABSTRACT

A HAND AUTOMATIC SAMPLER AND DILUTER ARRANGEMENT OPERABLE IN ANY POSITION AND INDEPENDENT OF GRAVITY, COMPRISING PASSING A ROLLER OVER A FIRST SECTION OF FLEXIBLE TUBING IN ORDER TO ASPIRATE A SAMPLE BY PERISTALSIS. A SECOND ROLLER PASSES OVER A SECOND SECTION OF TUBING OF WIDER DIAMETER TO EJECT THE SAMPLE PLUS SOME DILUENT. THE TWO SECTIONS OF TUBES ARE CONNECTED, BUT THE PERISTALTIC ACTION THROUGH THE SECTIONS MOVES IN OPPOSITE DIRECTIONS. IN PRACTICE, A SINGLE WHEEL WITH TWO ROLLERS ON OPPOSITE SIDES SERVES TO ALTERNATELY PASS OVER ONE AND THEN THE OTHER TUBING. THE INSTRUMENT IS SELF-CONTAINED, READILY PORTABLE, AND HAND OPERATED. A VALVE ARRANGEMENT PERMITS THE CLAMPING OF THE TUBING NEAR THE EXIT WHEN NEITHER ROLLER IS PRESSING THE TUBING.

Aug. 1, 1972 s. NATELSON HAND AUTOMATIC SAMPLER AND DILUTER Filed Aug. 19, 1970 l 3 Sheets-Sheet l W w m is m I g S. mm 3% if: MW e N M mmm N g m SAMUEL NATELSON ATTORNEY Aug; 1, 1972 s. NATELSON 3,681,030

HAND AUTOMATIC SAMPLER AND DILUTER Filed Aug. L9, 1970 3 Sheets-Sheet 2 FIG. 2B

- ATTORNEY Aug.- 1, 1972 s. NATELSON HAND AUTOMATIC. SAMPLER AND DILUTER 3 Sheets-Sheet 5 Filed Aug. L9, 1970 SAMUEL NATELSON INVENTOR.

ATTORNEY United States Patent O 3,681,030 HAND AUTOMATIC SAMPLER AND DILUTER Samuel Natelson, 5508 Hyde Park Blvd., Chicago, Ill. 60616 Filed Aug. 19, 1970, Ser. No. 65,146 Int. Cl. G01n 1/14, 31/00 US. Cl. 23-259 2 Claims ABSTRACT OF THE DISCLOSURE A hand automatic sampler and diluter arrangement operable in any position and independent of gravity, comprising passing a roller over a first section of flexible tubing in order to aspirate a sample by peristalsis. A second roller passes over a second section of tubing of wider diameter to eject the sample plus some diluent. The two sections of tubes are connected, but the peristaltic action through the sections moves in opposite directions. In practice, a single wheel with two rollers on opposite sides serves to alternately pass over one and then the other tubing. The instrument is self-contained, readily portable, and hand operated. A valve arrangement permits the clamping of the tubing near the exit when neither roller is pressing the tubing.

The invention described herein was made in the performance of work under a NASA contract and is subject to the provisions of Section 305 of the National Aeronautics and Space Act of 1958, Public Law 85-568 (72 Stat. 435; 42 U.S.C. 2457).

BACKGROUND OF THE INVENTION The present invention relates to an automatic sampler and diluter for use with small quantities of a sample which could be contained in the hand and be hand operated, and more particularly, to an automatic sampler and diluter used to sample a specimen of blood from the fingertip and then expel the specimen with the aid of water or a reagent so as to hemolyze the blood and dilute it for analysis.

BRIEF DESCRIPTION OF THE PRIOR ART The present instrument is useful with the arrangement described in the Samuel Natelson US. Patent No. 3,261,668. Automatic sampler and diluters available commercially operate by means of two sets of plungers. One plunger aspirates the specimen and the second ejects the specimen plus the diluent. These instruments generally require operation electrically by a motor and are too bulky and heavy to be used as a portable hand instrument.

SUMMARY OF THE INVENTION The present instrument resembles a flashlight in appearance and size. The diluent is retained in the handle of the instrument. The volume of diluent in the handle is or the order to 100-200 ml. Since, usually l '25 tl. is sampled and ejected with less than 100 l. of diluent, as many as 1000 samples can be sampled before the instrument needs to be refilled with diluent. The thumb rotates a wheel to sample and continues rotation in the same direction to eject the sample and diluent.

Generally speaking, the present invention contemplates passing a roller over a first section of flexible tubing in order to aspirate a sample by peristalsis. A second roller passes over a second section of tubing of wider diameter to eject the sample plus some diluent. The two sections of tubes are connected but the peristaltic action through the sections moves in opposite directions. In practice, a single wheel with two rollers on opposite sides serve to alternately pass over one and then the other tubing. Means is provided to prevent the siphoning out of the Patented Aug. 1, 1972 'ice diluent when neither roller is pressing the tubing. Also there are means for providing a continuous flow of diluent without injecting air or creating a vacuum in the system.

The invention, as well as other objects and advantages thereof will become more apparent from the following detailed description when taken together with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS DETAILED DESCRIPTION FIG. 1 shows a hand automatic sampler and diluter 11 with a gear wheel 13 which rotates on an axle 15. On opposite sides of gear 13 are two rollers 17 and 19. The tubing 8 rests on a platform 10 which is pivoted to the outer structure 12 of the hand held instrument and is spring loaded with a spring 14. The rollers 17 and 19 pass over the tubing 8 and push back the platform. In this way, excessive pressure is not brought to bear on the tubing 8. This movement of the platform 10 also serve a second function. When neither roller rests on the rubber tubing 8, the liquid could siphon out. This is prevented because when the rollers are not on the tubing, the platform is in the up position, held there by spring 14. This causes a piece of plastic to press on the exit tube preventing the siphoning of the fluid. The tubing is in a U-shape with two sections 21 and 23. Section 21 is narrower than section 23 and the two sections are connected.

The rollers 17 and 19 pass alternately over rubber tubing sections 20 and 23. When passing over tubing section 21, the sample is aspirated at plastic tip 24 of the tubing. When passing over wider tubing 23, diluent from a container 25 is pumped out so that the sample at the plastic tip 24 is delivered along with the diluent. The tubing rests on platform 10 which rocks on pivot 29. Spring 14 whose tension is adjustable by nut 32, pressing on washer 32A, keeps the end 12 of the rocker platform 10 down, except when the rollers 17 and 19 press on the tubing. Threaded bolt 323 which slides loosely through hole 320, and is bolted to an outside frame, (not shown) which remains stationary and rigid. The tubing passes under the instrument platform just before it leaves the instrument at 34.

It then passes in a loop, one leg of the loop passing between a projection valve 36, and the bottom of the platform. The projection valve is a solid piece of plastic anchored to the frame of the instrument and has an edge. The tubing then emerges from under the platform at 41 and goes on to the exit tip 24.

When the rollers 17 and 19 are off the tubing, the spring 14 pushes down on the platform causing it to pivot at 29. This serves to bring lower tubing segment 34 in contact with the rigid projection valve 36, as shown in the drawing. This projection valve 36 presses on one leg of the tubing going below the platform 10 and acts to seal the tube. This prevents liquid flow when the rollers are oif the tubing. Thus, along the travel path of the diluent from the container 25 are rollers 17 and 19 and then projection valve 36 formed by a rigid section. The outlet rubber tubing is held down and back and the projection valve 36 presses on the tubing before it acts as an out let tube. Thus, unless the rollers 17 and 19 are acting on the tubing, the tubing outlet is blocked by the valve. In

order to keep tubing in place, stops 38 are placed around the tubing so that the tubing cannot be pulled beyond the stop points 40 and 40A. The diluting fluid is retained in container 25 which is a plastic bag inside a plastic bottle 43 with a hole to the air. The bag collapses as diluent is removed. This occurs because the hole 42 permits air pressure to push on the outside of the plastic bag. This permits the operation of the instrument in any position and makes it independent of gravity.

Rotation of gear 13 is simplified by means of pinion gear 44 and knurled Wheel 46 arrangement. Wheel 46 is operated by the thumb, while the technician holds the barrel of the instrument containing the container 25.

The tubing 8 passes under the platform and back, so that a lower tubing segment 34 is underneath the platform. The platform moves up and down because of the pivot. When the rollers are olf the tubing, the spring 14 pushes the platform. Thiscauses the lower tubing exit segment 34 to be pressed against projection valve 36. This acts to stop the flow of liquid. When the rollers are off the rubber tubing, the valve is thus closed. When one of the rollers presses on the tubing because of the rocker or lever action, the opposite side moves up. This releases the pressure on the loop of lower tubing exit segment 34 under the platform and the liquid may now flow. The valve is located just before the exit of the fluid so that no flow can take place when rollers are off the tubing.

The instrument may operate in any position. The reservoir of diluting fluid is kept in an inner plastic bag 25. The plastic bag is protected by an outer plastic container 43 around it. This container has a hole 42 punched in it to equilibrate with ambient atmospheric pressure. A-s liquid is pumped out of the plastic bag, the plastic 'bag collapses. In this way, liquid will flow regardless of the orientation of the plastic bag or whether it is in a weightless environment.

The tubing in the hand automatic sampler and diluter may be replaced to change the volumes being sampled and ejected and the ratio of each to the other. For this purpose, Table I calculates the volume of fluid delivered per cm. of Tygon clear tubing. The color code is that of a readily available commercial tubing.

TABLE I Tube selection for automatic sampler and dlluter Values for volumes delivered by clear plastic Tygon tubing ID. ID. Volume per Color (tubing code) (inches) (cm.) cm. 1.)

Orange-black 005 0064 0. 13 Orange-red- 0075 0005 0. 28 Orange-blue... 010 0127 0. 51 Orange-green. 015 0191 1. l4 020 0264 2. 03 025 0318 3. l7 030 0381 4. 56 035 0445 6. 20 040 0508 8. l 045 0572 10. 26 051 0648 13. 17 056 0711 15. 88 060 0762 18. 23 065 0826 21. 40 073 0927 26. 90 081 1029 33. 23 090 1143 41. 02 100 1270 50.65 Purple-white 110 1397 61. 28

OPERATION OF INSTRUMENT The instrument shown in FIG. 1 has only one platform 10, and as a practical matter, one platform is all that the instrument should require. For ease of explanation of the principle upon which the device is based, however, two platforms 10A and 10B are shown in the schematic FIGS. 2A, 2B and 2C. Also, rollers 17A and 19A are not shown attached to a single 'wheel, two springs 14A and 14B are shown, and two valves 36A and 36B are shown acting on two sections of tubing which is over and not under the platform as in FIG. 1.

In FIG. 2A, roller 17A presses on tubing 23. This causes a sample held in a test tube 50 to be aspirated. The pressure of the roller 17 A causes the platforms 10A, 10B to move down against springs 14A, 1413. This releases valves 36A, 36B. Thus, pressure on the tube is released to open the tube. Since the lower platform 10A, as shown in FIGS. 2A to 2C is tied to the upper platform 10B by a connector, the tubing on the lower platform will also be opened so the movement of the fluid will be back to the diluent container.

When, as shown in FIG. 2B the rollers 17A and 19A are not acting on the tubing, the springs 14A, 14B push the valves 36A, 3613 against the tubing. The valve is pressed against the tubing after the rollers, i.e., the valve action takes place closer to the entrance or discharge end of the tubing.

In FIG. 2C, roller 19A presses and rolls across the tubing. Again the platforms 10A, 10B press against the springs, the roller acting on the wider leg of the tubing causes the tubing to open and to aspirate diluent which is ejected along with the original sample into the test tube acting as the sample receiver. Thus, FIG. 2A shows sampling and FIG. 2C shows ejection of the sample.

In FIG. 2A, movement of the wheel as shown will cause a sample to be aspirated. The pressure of the wheel on the support will cause it to move down against the spring and around the pivot. This simultaneously will release the pressure on the tube stop and open the tube. Since the lower platform is tied to the upper platform by a connector, the tubing will also be opened there so that movement of fluid Will be back to the diluent container.

In FIG. 2B, the wheel is not pressing on the tubing. The spring causes the tube stop clamps to close, clamping the tubing and preventing siphoning. In 'FIG. 2C, the wheel is now pressing and turning on the wider leg of the tubing. This causes the tubing to open and aspirates diluent which is ejected along with the original sample into the test tube acting as sample receiver.

I claim:

1. A light, portable, hand operated instrument for sampling a predetermined amount ofa liquid sample, and ejecting said sample with a predetermined amount of diluent, comprising in combination:

(a) a rocking platform defining an upper and an underneath portion with a pivot operatively engaging the platform so that the platform can rock, and spring means biasing one side of the platform downwards;

(b) a continuous length of tubing disposed on said platform in a U-shape with first and second parallel arm sections passing across said platform upper portion and a tubing segment passing through the platform and across said underneath portion, the bore diameter of the first arm section being smaller that that of the second arm section, said tubing segment being connected to the first arm segment and having a narrow exit at its other end capable of being dipped into a liquid sample;

(c) projecting valve means disposed under said underneath portion which will apply against said lower tubing segment because of said spring bias rocking said platform on its pivot against said projecting valve means;

((1) a wheel disposed over said upper platform portion with the Wheel periphery passing between said first and second tubing sections, hand operable means to turn said wheel, a press roller on each side of said wheel periphery angularly offset *from each other disposed to apply pressure on said first and second tubing sections, said wheel pressure removing said spring bias by rocking said platform on said pivot away from said projecting valve means and preventing said valve means from acting on said tubing; and,

(e) a reservoir for holding a diluent connected to the second tubing section, said reservoir comprising an outer rigid chamber, wig an opening to the atmos- H References Cited phere, an inner chamber with a flexible wall pro- UNITED STATES PATENTS 1 tested by said outer chamber so that said wall will 3,184,122 5/1965 Nerenberg 23 259 X collapse progressively under air pressure as liquid is 5 3,284,164 11/1966 Hach 23-253 removed from said inner chamber, permitting the in- 3,297,558 1/1967 Hillqllist X strument to be used in any direction independent of g2 gravity- 3,4s4j207 12/1969 Anthon 23 2s3 2. An instrument as claimed in claim 1, said wheel be- 10 J SCOVRONEK Primary Examiner ing a gear wheel, gearing to turn said gear wheel and said hand operable means being a finger rotatable secmm 232s3 R; 73-4255; 417-471 

